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2006 2017

Modulated reflectance (contactless electroreflectance (CER), photoreflectance (PR), and piezoreflectance (PzR)) has been applied to study direct optical transitions in bulk MoS[subscript 2], MoSe[subscript 2], WS[subscript 2], and WSe[subscript 2]. In order to interpret optical transitions observed in CER, PR, and PzR spectra, the electronic band structure for the four crystals has been calculated from the first principles within the density functional theory for various points of Brillouin zone including K and H points. It is clearly shown that the electronic band structure at H point of Brillouin zone is very symmetric and similar to the electronic band structure at K ...

Contributors
Kopaczek, J., Polak, M. P., Scharoch, P., et al.
Created Date
2016-06-21

Chemical vapor deposition methods were developed, using stoichiometric reactions of specialty Ge[subscript 3]H[subscript 8] and SnD[subscript 4] hydrides, to fabricate Ge[subscript 1-y]Sn[subscript y] photodiodes with very high Sn concentrations in the 12%–16% range. A unique aspect of this approach is the compatible reactivity of the compounds at ultra-low temperatures, allowing efficient control and systematic tuning of the alloy composition beyond the direct gap threshold. This crucial property allows the formation of thick supersaturated layers with device-quality material properties. Diodes with composition up to 14% Sn were initially produced on Ge-buffered Si(100) featuring previously optimized n-Ge/i-Ge[subscript 1-y]Sn[subscript y]/p-Ge[subscript 1-z]Sn[subscript z] type ...

Contributors
Senaratne, Charutha Lasitha, Wallace, Patrick, Gallagher, John, et al.
Created Date
2016-07-13

We define the dielectric constant (susceptibility) that should enter the Maxwell boundary value problem when applied to microscopic dielectric interfaces polarized by external fields. The dielectric constant (susceptibility) of the interface is defined by exact linear-response equations involving correlations of statistically fluctuating interface polarization and the Coulomb interaction energy of external charges with the dielectric. The theory is applied to the interface between water and spherical solutes of altering size studied by molecular dynamics (MD) simulations. The effective dielectric constant of interfacial water is found to be significantly lower than its bulk value, and it also depends on the solute ...

Contributors
Dinpajooh, Mohammadhasan, Matyushov, Dmitry, College of Liberal Arts and Sciences, et al.
Created Date
2016-07-06

Singly deuterated silylene has been detected and characterized in the gas-phase using high-resolution, two-dimensional, optical spectroscopy. Rotationally resolved lines in the 0[0 over 0][˜ over X][superscript 1]A′ → [˜ over A][superscript 1]A′′000X˜1A′→A˜1A″ band are assigned to both c-type perpendicular transition and additional parallel, axis-switching induced bands. The extracted rotational constants were combined with those for SiH[subscript 2] and SiD[subscript 2] to determine an improved equilibrium bond length, r[subscript SiH], and bond angle, θ, of 1.5137 ± 0.0003 Å and 92.04° ± 0.05°, and 1.4853 ± 0.0005 Å and 122.48° ± 0.08° for the [˜ over X][superscript 1]A′(0, 0, 0) and ...

Contributors
Kokkin, Damian, Ma, Tongmei, Steimle, Timothy, et al.
Created Date
2016-06-27

Dengue virus (DV) infections cause undisputedly the most important arthropod-borne viral disease in terms of worldwide prevalence, human suffering, and cost. Worldwide DV infection prevalence in 2010 was between 284 to 528 million cases. Approximately 84% of these cases come from Asia and the Americas, where the cost for emerging economies can be as high as 580 million dollars per year. Thus, the need for an efficient vaccine against DV is extreme.

Contributors
Maria del Angel, Rosa, Reyes del Valle, Jorge, College of Liberal Arts and Sciences, et al.
Created Date
2013-10-03

α-(1,3)-Glucan is a major component of the cell wall of Aspergillus fumigatus, an opportunistic human fungal pathogen. There are three genes (AGS1, AGS2 and AGS3) controlling the biosynthesis of α-(1,3)-glucan in this fungal species. Deletion of all the three AGS genes resulted in a triple mutant that was devoid of α-(1,3)-glucan in its cell wall; however, its growth and germination was identical to that of the parental strain in vitro. In the experimental murine aspergillosis model, this mutant was less pathogenic than the parental strain. The AGS deletion resulted in an extensive structural modification of the conidial cell wall, especially ...

Contributors
Beauvais, Anne, Bozza, Silvia, Kniemeyer, Olaf, et al.
Created Date
2013-11-14

Community associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a major cause of skin and soft tissue infections (SSTIs) in the US. We developed an age-structured compartmental model to study the spread of CA-MRSA at the population level and assess the effect of control intervention strategies. We used Monte-Carlo Markov Chain (MCMC) techniques to parameterize our model using monthly time series data on SSTIs incidence in children (≤19 years) during January 2004 -December 2006 in Maricopa County, Arizona. Our model-based forecast for the period January 2007–December 2008 also provided a good fit to data. We also carried out an uncertainty and ...

Contributors
Wang, Xiaoxia, Panchanathan, Sarada, Chowell-Puente, Gerardo, et al.
Created Date
2013-11-21

The optical properties of intersubband transition in a semipolar AlGaN/GaN single quantum well (SQW) are theoretically studied, and the results are compared with polar c-plane and nonpolar m-plane structures. The intersubband transition frequency, dipole matrix elements, and absorption spectra are calculated for SQW on different semipolar planes. It is found that SQW on a certain group of semipolar planes (55° < θ < 90° tilted from c-plane) exhibits low transition frequency and long wavelength response with high absorption quantum efficiency, which is attributed to the weak polarization-related effects. Furthermore, these semipolar SQWs show tunable transition frequency and absorption wavelength with ...

Contributors
Fu, Houqiang, Lu, Zhijian, Huang, Xuangqi, et al.
Created Date
2016-05-05

Acute Myeloid Leukemia (AML) is a fatal hematological cancer. The genetic abnormalities underlying AML are extremely heterogeneous among patients, making prognosis and treatment selection very difficult. While clinical proteomics data has the potential to improve prognosis accuracy, thus far, the quantitative means to do so have yet to be developed. Here we report the results and insights gained from the DREAM 9 Acute Myeloid Prediction Outcome Prediction Challenge (AML-OPC), a crowdsourcing effort designed to promote the development of quantitative methods for AML prognosis prediction. We identify the most accurate and robust models in predicting patient response to therapy, remission duration, ...

Contributors
Noren, David P., Long, Byron L., Norel, Raquel, et al.
Created Date
2016-06-28

Thousands of mothers are at risk of transmitting mitochondrial diseases to their offspring each year, with the most severe form of these diseases being fatal [1]. With no cure, transmission prevention is the only current hope for decreasing the disease incidence. Current methods of prevention rely on low mutant maternal mitochondrial DNA levels, while those with levels close to or above threshold (>60%) are still at a very high risk of transmission [2]. Two novel approaches may offer hope for preventing and treating mitochondrial disease: mitochondrial replacement therapy, and CRISPR/Cas9. Mitochondrial replacement therapy has emerged as a promising tool that ...

Contributors
Fogelman, Sarah, Santana, Casey, Bishop, Casey, et al.
Created Date
2016-08-30